Diagnostic Aids

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The Intake Air Humidity Signal parameter displays the measured humidity within the air intake system and may differ from atmospheric humidity measured outside the air intake system.
The humidity sensor and the IAT sensor 2 signals are sent to the ECM on the same circuit. If the Intake Air Humidity parameter displays the value : 0% or 100%, and there are also IAT Sensor 2 DTCs, check for a circuit problem.